1. Technical Field
Embodiments of the present invention relate to an image forming apparatus including a powder container accommodating powder for image forming, and a powder transport unit to transport the powder in the powder container.
2. Related Art
Electrophotographic image forming apparatuses typically include development devices that develop an electrostatic latent image with powder toner into a visible image. The toner is refilled in response to an amount of toner consumption in each development device, typically by replacing each toner cartridge, as disclosed in Japanese Patent Publication JP-4673643-B (JP-2006-243446-A). When installing the toner cartridge in an image forming apparatus, an outlet of the toner cartridge is connected to an inlet of the development device, so that new toner is supplied from the toner cartridge to the development device.
Some development devices include an optical sensor to detect the amount of toner in the development device, as disclosed in Japanese Patent Application Publication JP-2006-284747-A. Based on the detection results obtained by the optical sensor, the toner is supplied form the toner cartridge to the development device when requested.
FIG. 1 illustrates a known development device in a state in which an amount of toner supplied to a toner cartridge has reached above an upper limit of an inlet thereof.
In a development device 200 without such an optical sensor or any other detector for detecting the maximum level of toner therein, toner T can reach a present toner level A0 beyond a position B0 that is the maximum toner level to be supplied through an inlet 200a of the development device 200, as illustrated in FIG. 1.
When disconnecting the toner cartridge from the development device 200 with the toner therein reaching above the position B0, it is likely that the toner falls out of the development device 200 through the inlet 200a and the fallen toner scatters to contaminate the interior of the image forming apparatus.